›› 2009, Vol. 21 ›› Issue (3): 0-273.

• 论文 •    

黑曲霉β一甘露聚糖酶的诱变选育及部分酶学特性

许少春,李艳丽,柳 永,汤江武,许尧兴*   

  1. 浙江省农业科学院植物保护与微生物研究所,浙江杭州310021
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2009-05-25 发布日期:2009-05-25

Strain screening of β-mannanase and enzyme properties

XU Shao-chun;LI Yan—li;LIU Yong;TANG Jiang-wu;XU Yao-xing*   

  1. Plant Protection and Microbiology Institution, Zhejiang Academy of Agricultural Sciences,Hangzhou 310021,China
  • Received:1900-01-01 Revised:1900-01-01 Online:2009-05-25 Published:2009-05-25

摘要: 从实验室保藏的数十株真菌、细菌和酵母菌种中,经定向筛选,得到1株产β-甘露聚糖酶酶活较高的黑曲霉菌株MA。以菌株MA为出发菌,经Co60诱变和摇瓶发酵初、复筛,最终获得一株产 β-甘露聚糖酶活力高且遗传性能稳定的菌株MA-56,其所产的β-甘露聚糖酶活力稳定在9.31×l0 4 U/g,较出发菌株提高了64.78%。酶学性质初步研究表明,黑曲霉菌株MA-56所产甘露聚糖酶的最适反应温度为70℃,最适反应pH为2.5~3.5;该酶在70℃以下具有良好的热稳定性,在pH2.5~9.0的环境下表现稳定;在供试的10种金属离子中,只有Cu2+ 对酶活有较强的抑制作用。

关键词: β-甘露聚糖酶, 黑曲霉, Co60定向诱变, 酶学性质

Abstract: Aspergillus niger MA was selected as the initial strain for β-mannanase production from a number of strains.After Co 60 mutagenesis of A.niger MA,a genetic stable and β-mannanase overproducing mutant A.niger MA-56 was obtained through primary and secondary screening.The activity of β-mannanase was improved about 64.78% and reached 9.31× 10 4 U/g.The results of enzyme characteristics of β-mannanase showed that the optimum temperature was 70℃ and the optimum pH was 2.5—3.5.Moreover,β-mannanase was also stable at pH 2.5—9.0 at 60℃ .Among different metal
ions,Cu2+ showed stronger inhibitory effect on the activity of β-mannanase.

Key words: β-mannanase, Aspergillus niger, Co 60 mutagenesis, enzyme characteristics